Door closer



Feb.' 19, 1952 B. H. WOODRUFF DOOR CLOSER Filed Oct. 15, 1949 2 SHEETSSHEET l 5 4 5 3 5 8 5 5 7 w m 4 m w T M G 8 .4 M V 4 4 4 WI "u L w a a m M; m A

2 4 l O. U 4 4 A TTORNE Y Feb. 19, 1952 B. H. WOODRUFF DOOR CLOSER 2 SHEETS-SHEET 2 Filed 001. 15, 1949 INVENTOR.

ATTORNEY Patented Feb. 19, 1952 UNITED STATES PATENT OFFICE DOOR CLOSER Ben H. Woodrufi, Chicago, 111.

Application October 15, 1949, Serial No. 121,469

8 Claims.

This invention relates to a door closer of the type that is applied to a door for controlling the closin speed of the door as the door is moved to a closed position by a spring or other power mechanism.

In door closers of the particular class, it is customary to mount a piston for movement in a cylinder or chamber, with fluid maintained in the cylinder or chamber and moved by the piston through a valved passage as the piston moves from a position corresponding to the open position of the door to a position corresponding to the fully closed position of the door. By regulating the valved passage, the door closing speed is fully and completely controlled.

In door closers of the class described, once the door is moved to a full open position, there is a tendency for the power closing mechanism, such as a spring, to close the door rather rapidly under the control of the piston and the valved passage described. Such closing movement of the door makes it diflicult for one to pass through the door without holding the door manually open during the passing movement against the pressure of the door closing power means. Therefore, where the person passing through the door is carrying a tray or bulky package and cannot hold the door open, it frequently happens that the door will close so rapidly as to strike that person. It is the object of my invention to contribute to the art a door closer that will act to maintain the door in substantially a full open position for a short interval of time once the door is opened, after which to close the door in the usual manner of prior art structures. It is a further object of my invention to contribute a door closer allowing such predetermined positioning of the door in open position, while utilizing an extremely simple mechanism and not requiring a complete reorganization and revision of the standard commercial door closer well known in the art.

As a feature of my invention, I provide a free passage through which fluid flows from the usual speed controlling valved passage to the low pressure end of the chamber or cylinder in which the control piston moves. Thus, the high pressure end of the chamber or cylinder is that end toward which the piston moves incidental to the closin movement of the door, while the low pressure end is that end of the chamber towards which the piston moves during the opening movement of the door. Fluid will flow through the free passage from'the valved passage incidental to the door closing movement and without in any way affecting the speed of the door closing movement, that being controlled by the valved passage. However, the free passage is closed by the piston when the piston is moved to a position corresponding to the full open position of the door. Therefore, when the door is open, fluid cannot flow through the free passage from the valved passage, except as hereinafter set forth, and the door will be maintained open.

To provide for some slight closing speed so as to initiate the closing movement of the door, I provide a control passage that is in parallel or bypass relation to the free passage, and through which fluid may flow to the low pressure end of the cylinder or chamber in which the piston moves. The control passage is suitably controlled by a valve so as to determine the speed of the flow of the fluid, and therefore determine fully the interval of time that the door will be maintained substantially in its open position, once it is moved to the said open position.

I have thus outlined rather broadly the more important features of my invention in order that the detailed description thereof that follows may be better understood, and in order that my contribution to the art may be better appreciated. There are, of course, additional features of my invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will anpreciate that the conception on which my disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of my invention. It is important, therefore, that the claims to be grant-- ed me shall be of suflicient breadth to prevent the appropriation of my invention by those skilled in the art.

Referring now to the drawings, Fig. 1 is a perspective view showing a door closer embodying my invention applied to a door and frame. Fig. 2 is a horizontal section through the door closer of my invention. Fig. 3 is a section taken along lines 3--3 of Fig. 2. Fig. 4 is a view of the parts of Fig. 2 with the piston approaching the high pressure or closing end of the cylinder in which it operates. Fig. 5 is a perspective view of the two parts comprising the valve for the control passage.

Referring now more particularly to the drawings, the door closer of my invention is shown applied to the frame ll] of a door as best seen in Fig. 1. The door closer construction per se i s identical with that of the Norton Patent No. 1,152,339, but it should be understood that my invention is applicable to other types of door closers including not only the rack and pinion type of Norton, but the crank type, the win piston type, etc.

In Fig. 1, the door closer is shown comprising an integral bracket H whereby it may be bolted through bolts l2 to the door frame I9. A usual type of lever arm 53 is pivoted at l4 to a bracket I5 that is secured to the door i6 for movement with the door upon opening and closing movement thereof. Lever arm I3 is pivoted at I? to an arm l9 that is secured to the main rotating shaft l9 of the door closer best shown in Figs. 2 and 4.

Main shaft [9 has secured thereto a pinion 29 that is maintained in geared relation to a rack 24 forming part of the control piston of my door closer, said control piston being in turn designated generally by reference numeral 22. Control piston 22 has a head 23 and a further head 24. It is the fuction of the head 23 to control the closing movement of the door while the head 24 acts to control the final opening movement of the door. Further, because the piston has two heads, the closer is reversible as those skilled in the art will appreciate.

It is the function of the shaft I9 through its pinion 26 to move the piston 22 from a position just to the left of its position at Fig. 4 to its position of Fig. 2, as the door moves from closed to open position. During this movement, the shaft i9 functions to wind a suitable spring maintained in the cylindrical part 25 of the door closer seen in Fig. 1.

Piston 22 operates in a cylindrical chamber 26, one end of the said chamber being closed by a cap 21 while the other end is closed by a cap 28. Fluid is contained within the said chamber 25 for movement by the piston 22 through its heads 23 and 24. Mounted within the head 23 is a ball valve 29 adapted to close a passage 39 during movement of the piston head 23 toward the left in Figs. 2 and 4. Similarly, ball valve .3! closes a passage 32 in the piston head 24 during movement of the piston to the right from the position of Fig. 4 to the position of Fig. 2. When the piston heads are moving in a reverse direction to that just outlined, fluid will flow freely through the bores 39, 32 and past the said ball valves 29 and 3i. For maintaining the ball valves 29 and 3i against movement out of the piston heads 23 and 24, suitable retaining pins 33 are utilized as those skilled in the art will fully understand.

Extending from the left side of the chamber 26, as clearly shown in Figs. 2 and 4, are bores 34 and 35 leading to a bore 36 within which is mounted a valve body 31, bored at 38 for a valve stem 39. Valve stem 39 has at its outer end an integral head 40, slotted at 4| for a screw driver whereby it may be rotated relatively to a threaded sleeve 42. Sleeve 42 is in turn secured through threads 43 to the door closer casting. It is the function of the sleeve 42 to mount the valve stem 39 for movement of adjustment While simultaneously holding in place suitable stufling material 44. It is the function of the valve stem 39, in conjunction with the remaining parts just described, to control the speed of movement of fluid from the chamber 26 as the piston head 23 moves from its position of Fig. 2 to its position of Fig. 4.

Thus, during this movement of the piston 22 and its head 23, fluid will flow from the chamber 26 through passages 34 and 35 until the piston reaches the position of Fig. 4. Thereafter, fluid will flow only through passage 34 and thence through the bore 38 of the valve body 3'! at a speed determined by valve stem 39.

Insofar as I have described my invention, it is quite old and well known in this art. Thus, the fluid normally flows from the bore 38 as just described, into a large passage 45 and thence to the low pressure side of the piston 22. If, in Fig. 2, passage 45 were shown completely open for its full length so as to allow free fiow of fluid into chamber 46, we would have the construction of a prior art door closer as set forth in the Norton patent to which I earlier alluded. I shall now describe the function of my invention and the construction of the parts which must be added to the standard Norton door closer for obtaining theresults I believe are so very valuable.

In carrying out my invention I form a bore 4'! in the closer casting leading from the outside of the door closer into the chamber or cylinder 26 and traversing passage 45. The bore 41' is preferably but not necessarily formed so that its inner end 41a is smaller in diameter than its outer end. I force into the bore 4'! a sleeve 48 shown best in Fig. 5, and blocking passage 45 as seen in Fig. 3. The sleeve 48 is formed with an internal bore 49 somewhat enlarged at 50 and there threaded for the threaded portion 5| of an adjusting valve 52. The stem of the valve 52 is formed with a bore 53 adapted to allow flow of fluid through a slot 48a in the sleeve 48, the bore 53, and thence through a further bore 55 in the said sleeve 48.

The bore 51 is so located that its end 41a will be substantially closed by the piston head 23 when the door is moved to open position. This position is illustrated in Fig. 2, and it is quite well and readily appreciated that with the parts in the particular position, fluid cannot flow through the normal free passage including passage 45, slot 48a, bores 49 and 41a. Nor can fluid flow as in prior art closers to chamber 46 and then to the piston chamber 26. Therefore, when the door is open and the parts are in the position of Fig. 2, there is no way for the fluid to escape from the chamber .26 except through the small bore 53 in the valve stem 52. The valved passage formed by bore 53 provides with the bore 55 and the chamber v46 an escape passage that is parallel to the free passage 48a, 49, 47a so that some flow from the cylinder 26 may occur.

In one particular position of the valve stem 52, the bore 53 may be partially closed relatively to the bore 55 of the sleeve 48. Therefore, a relatively considerable period of time will be required for a very small amount of fluid to move from the cylinder 26 through the valved passage 36, the slot 48a, bore 53, and thus to the chamber 46. Therefore, when the door is in fully opened position, it will be appreciated that the spring in the chamber 25 will be unable to move the piston 22 and the shaft [9 in a door closing direction, except at an extremely slow speed. However, fluid will eventually escape through the small bore 53 in valve stem 52 insufficient volume to allow movement of the piston head beyond the bore 41a of large bore 41. Thereupon, the relatively free passage of fluid will be possible through passage 45, slot 48a and bores 49 and 41a. Therefore, a relatively fast closing of the door will be obtained under the control of the valve stem 39 as in other door closers of the rack and pinion type.

It is, therefore, seen that by merely equipping the usual door closer such as shown in the Norton patent with the parts of Fig. 5, and placing those parts in particular relation to the piston head 23 of piston 22, I make it possible for the door to be maintained in full open position for a relatively considerable period of time so that free passage through the doorway controlled by the door I6 is made possible. Only after some time in the open position will the door It equipped with my door closer be moved to fully closed position in the usual way. I believe that the very considerable merits of my invention and the relatively inexpensive means that are utilized for making it possible, will now be fully appreciated by those skilled in this art.

It should be emphasized further that while my closer makes possible the advantages outlined, I still maintain the inherent operations of the prior art that are considered so desirable, including the door opening check made possible by the doubleended construction of the piston 22 and chamber 26 combined with valves at each end thereof.

I now claim:

1. In a door closer, a moving piston, said door closer having a fluid containing chamber in which said piston moves, means for moving said piston in said chamber incidental to the opening and closing of a door to be controlled, said door closer having a speed control passage in communication with said chamber and through which fluid is forced by said piston from said chamber as said piston moves in a door closing direction in said chamber, a valve for controlling the speed of fluid movement in said speed control passage, a free passage in communication with said speed control passage and through which the fluid flows from said speed control passage towards the rear of said piston as said piston moves in a door closing direction, a portion of said piston closing said free passage when said piston is moved to a position corresponding to the open position of the door, said portion of said piston opening said free passage once said piston moves a short distance from said open position toward door closing position, and a valved passage com municating with said speed control passage and said chamber and in parallel relation to said free passage and through which fluid flows from said speed control passage during the movement of said piston from said open position to a position opening said free passage.

2. In a door closer, a moving piston, said door closer having a fluid containing chamber in which said piston moves, means for moving said piston in said chamber incidental to the opening and closing of a door to be controlled, said door closer having a free passage in communication with said chamber and through which fluid is forced by said piston from said chamber as said piston moves in a door closing direction with said fluid moving through said free passage toward the rear of said piston, a portion of said piston closing said free passage when said piston is moved to a position corresponding to the open position of the door, said portion of said piston opening said free passage once said piston moves a short distance from said open position toward door closing position, and a valved passage communicating with said free passage and said chamber and in parallel to said free passage through which fluid flows during the movement of said piston from said open position to a position opening said free passage.

3. In a door closer, a moving piston, said door closer having a fluid containing chamber in which said piston moves, means for moving said piston in said chamber incidental to the opening and closing of a door to be controlled, said door closer having a speed control passage and a 6.. valved passage in series relation and in communication with said chamber and through which fluid is forced in sequence by said piston from said chamber as said piston moves in a door closing direction with said fluid moving towards the rear of said piston, a free passage in by-pass relation to said valved passage, said iston closing said free passage when said piston is moved to a position corresponding to the open position of the door whereby the flow of fluid from said chamber through said free passage is prevented and fluid flows only through said speed control passage and valved passage under the influence of said piston, said piston opening said free passage once said piston moves a short distance from said open position toward doo closing position so that fluid then flows through said control passage and free passage under the influence of said piston.

4. In a door closer, a moving piston, said door closer having a fluid containing chamber in which said piston reciprocates between a position corresponding to the closed position of a door to which said closer is attached, and the open position of said door, means for movin said piston incidental to the opening and closing of a door to be controlled, said door closer having a speed control passage in communication with said chamber and through which fluid is forced by said piston from said chamber as said piston moves toward said position corresponding to the closed position of said door, a valve for controlling the speed of fluid movement in said speed control passage, a free passage in communication with said speed control passage and through which the fluid flows from said speed control passage toward the functional rear of said piston as said piston so moves, a portion of said piston closing said free passage when said piston is in a position corresponding to the open position of the door, said portion of said piston opening said free passage once said piston moves a short distance from said open position toward door closin position, and a valved passage communicating with said speed control passage and said chamber and in parallel relation to said free passage and through which fluid flows from said speed control passage during the movement of said piston from said open position to a position opening said free passage.

5. In a door closer, a moving member, said door closer having a fluid containing chamber in which said member moves, means for moving said member in said chamberincidental to the opening and closing of a door to be controlled, said door closer having a speed control passage in communication with said chamber and through which fluid is forced by said member from said chamber as said member moves in a door closing direction in said chamber, a valve for controlling the speed of fluid movement in said speed control passage, a free passage in communication with said speed control passage and through which the fluid flows from said speed control passage towards the rear of said member as said member moves in a door closing direction, means whereby said member closes said free passage when said member is moved to a position corresponding to the open position of the door, and opens said free passage when said member moves a short distance from said open position toward door closing position, and a valved passage in parallel relation to said free passage and through which fluid flows from said speed control passage durin the movement of said member from said open position to a position opening said free passage.

6. In a door closer, a moving member, said door closer having a fluid containing chamber in which said member moves, means foremoving said member in said chamber incidental to the opening and closing of a door to be controlled, said door closer having a speed control passage in communication with said chamber and through which fluid is forced by said member from said chamber as said member moves in a door closing direction in said chamber, a valve for controlling the speed of fluid movement in said speed control passage, a free passage in communication with said speed control passage and through which the fluid flows from said speed control passage towards the rear of said member as said member moves in a door closing direction, said member effecting the closing of said free passage when said member is moved to a position corresponding to the open position of the door and the opening of said free passage when said member moves a short distance from said open position toward door closing position, and avalved passage communicating with said speed control passage and said chamber and in parallel relation to said free passage and through which fluid flows from said speed control passage during the movement of said member from said open position to a position opening said free passage.

7. In a door closer, a moving member, said door closer havin a fluid containing chamber in which said member moves, means for moving said member in said chamber incidental to the opening and closing of a door to be controlled, said door closer having a free passage in communication with said chamber and through which fluid is forced by said member from said chamber as said member moves in a door closing direction with said fluid moving through said free passage toward the rear of said member, means whereby said member efiects the closing of said free passage when said member is moved to a position corresponding to the open position oi" the door and effects the opening of said free passage when said member moves a short dis,- tance from said open position toward door close ing position, and a valved passage in parallel to said free passage through which fluid flows during the, movement of said member from said openposition to a position opening said free pas,- sae 8. In a door closer, a moving member, said door closer having a fluid containing chamber in which said member moves, means for moving said member in said chamber incidental to the opening and closing of a door to. be controlled,

said door closer having a valved passage and a free passage in series with one another and in communication with said chamber and through which fluid is forced by said member from said chamber as said member moves in a door closing direction with said fluid moving first through said valved passage and then said free passage towards the rear of said member, means whereby said member efiects the closing of said free pas,- sage when said member is moved to a position correspondin to the open position of the door whereby the flow of fluid from said chamber through said valved passage and free passage is prevented, a further valved passage in by-pass relation to said free passage through which fluid flows while said free passage is closed, said member effecting the opening of said free passage when said member moves a short distance from said open position toward door closing position while moving said fluid through said further valved passage.

BEN H. WOODRUFF.

REFERENCES CITED Name Date Norton July 8, 1930 Number 

